 Hi, I'm Nate Adams, often known as Nate the House Whisperer, and this is an old presentation that I gave back in 2018, but it's useful information and I wanted to record it. So these are some lessons that we learned using indoor air quality monitors. So we're going to talk about three different little areas here. Mold sensitivity reduction, balancing temperature between floors, and what happens when you ventilate a spray foam job. So we used, and here's the original slide deck, we used Fubot air quality monitors, which sadly aren't available on the market anymore. They have moved from residential to commercial, but we learned a lot from these and we had a lot of them out there. So we had about 40 monitors out, typically three per home, one per floor, so basement first floor, second floor, and we learned a great deal that led to the development of bad ass HVAC. We figured out where the main weaknesses were and we tried to mitigate them with the system and it'll do it naturally. So let's start with mold sensitive case studies. So this client has a severe mycotoxin allergy, so he is allergic to what is in or what mold gives off. It was really debilitating for him, it would take him out for days with like a bad flu. He was considering going on permanent disability, which really would have stunk. Both these clients are extremely intelligent and they just needed problems to work on. And that would not have been a good thing. And that's the hard part with environmentally sensitive clients. It's usually pretty emotional. I'm not focused as much on the actual physical problems that I'm trying to solve in the house. Oftentimes, I'm focused on trying to help the clients themselves and that makes the work pretty challenging. So but when we tested in this house with the Bloorador to see how leaky the house was to understand what the path forward is going to look like, I asked permission. We did a depressurization. His wife and I both got splitting headaches within moments of turning the Bloorador on, which was pretty wild. I've never had that happen before. So there was some bad stuff growing in the walls of that place. And the client was down for the count for a couple of days starting the next day. So it takes him usually about a day after exposure to really go down. So what we did to this house, we did a ventilating dehumidifier, which meant we were pressurizing the house slightly. We were dehumidifying and we were bringing in outdoor air. And they had already a new modulating York furnace and at the time York did not have a variable speed heat pump. So we put in a two stage heat pump, added better filtration, and that also helped with load matching. So these are all parts of the six functions of HVAC and what badass does. So this was basically a badass system. So here is the dehumidifier going in. We hung it from the roof choice. You can see these are spring loaded straps. And this is the fresh air intake outside. And here is that heat pump. And a heat pump is just an air conditioner. It can just go both ways. So it can heat and cool. So let's take a look at the IEQ readings. So this is two Fubots running. Note the gray line at 300 parts per billion. That is the threshold for that product. And the green is first floor, orange is second. Note how spiky it is in general. So the readings are all over the place. So the orange lines, it's not going substantially through the threshold that often. But going back to the first floor, the first floor definitely does go through the threshold pretty often. So after the job, this was pretty wild to see. So now the colors mean something different, orange is second floor, green is first and blue is basement. But it's kind of cool. You can see when things correlate and they generally hold together. You can also see that through here, these spikes, the basement is not correlating well with the first and second floor, which means the air down there was not mixing that heavily. So this big spike, this is the HVAC install. And the chemicals in the caulk for sealing the duct right around the heat pump were pretty stinky. So there was all kinds of stuff going on. We got a very high spike. But note what happens afterwards. Everything just basically flat lined and the spikes are now much smaller. So there's before and there's after. And the scale is actually a bit higher here because it spikes so high. But at the time, we had no immediate feedback loops to understand if what we were doing was working. And this was a revelation to be like, holy cow, I can't believe this worked. So these were the first three that we had out there. So this was a very early lesson. You can see it goes back to June of 16. We had pretty tight humidity control. So basements are always going to run a little bit higher relative humidity because they're cooler, which means higher relative humidity. But you can see we had decent humidity control. And this is, you can see it's going up and down for every day. So typically at night, humidity levels increase because the air condition is not running. And then during the day, they pull down. Here's the PM, the dust or particulates, and note that there were some spikes. So this was the job here. But this is something that just had happened. Look how flat all of that is. And when there are spikes, they blunt very quickly because of that continuous filtration. So this is why you want a good filter and your fan running as much as possible. And the good news was these readings correlated with client experience because we need both. So shortly afterwards, we got this email back, the new system's great, the air is much better. This was the really interesting thing. So they had a bunch of air quality monitors in addition to the Fubot, in fact, they gave me one that they didn't like and I verified that it wasn't very good. It was a cheap Chinese one. It didn't read until things were really bad for particulates and then it read about 3x what everything else was saying. So anyway, he said, our carbon dioxide levels have been consistently between 500 and 700 parts per million when we wake up in the morning before they were in the 1,500 range. I've been waking up feeling rested for a change and with clear sinuses to boot. So it's looking good. That was really cool to see. Humidity levels are very stable. Temperature is much more stable. That's load matching and equipment that's running a lot. So it's a good thing. In terms of symptoms, I've been sleeping a lot better and haven't experienced any of my symptoms since coming back. So while the job was going on, he went to visit his brother so that he wouldn't be exposed to what was going on and that was great that he was feeling better. So we got to mix objective and subjective, which was great to have that feedback loop. So we had the client giving us subjective feedback and then we had objective measured feedback as well. Now next little thing I wanted to talk about, this is balancing temperatures between floors and this is back before you could get Fahrenheit on the system. And you can see which ones are which. So upstairs is green, downstairs is blue, and the basements is orange. So note how these were running fairly far apart, a couple degrees apart. We teach our clients as long as you have pressure to give, so it's called duct pressure or static pressure. If your fan is too big for the duct system, it's going to die early if it's a newer piece of equipment. So you have to be careful adding too much back pressure to them. But if you have headroom, you can play with your dampers and choke off some rooms partially to send more air to the rooms that aren't heating or cooling well. And that's what this client did. So you can see how the temperatures were different here and then they start being very, very similar to each other here. Okay, three different spray foam examples. So this first one, the client was out of the country actually as we did this. And it was early December. So I didn't want to leave windows open or anything like that to ventilate because there were a bunch of very cold days in the forecast. I didn't want to freeze pipes and then ruin the guy's house. So this was the first piece of the job. We were spraying in the garage, that's a split level house. So above this are the bedrooms. And this is Gary Smith of Affordable Foam playing around. He was running around me as I took this picture. But here's the interesting piece. So this is where the job happened and you can see that the VOCs went up quite high and we left the house entirely closed up. So it was only natural ventilation and the house at this time was actually still pretty leaky because we had only dealt with the garage. We hadn't dealt with the rest of the house yet. But it took two weeks for those levels to come down. So spray foam has bad chemicals in it. It's not very nice stuff. But if you don't ventilate, it takes two weeks for those chemicals to come out. So here you go. Here's Tuesday, November 29th to Sunday, December 11th. So just shy of two weeks before levels came back to normal. Now what happens if you ventilate with a blower door, which is our standard practice? And so we try to do these jobs when the weather is decent so that you can blow air in. So this is a client home. And here's kind of a fun thing. Where's the job in this chart? And the answer, I'll show you in a minute, but these spikes here, these are in the client's bedroom because they didn't have forced air at this point. Or they did, but they weren't using it for mixing it all. So the CO2 levels in the bedroom every night were driving up the VOCs, because the VOC sensors are usually cross-sensitive to, or sorry, the VOC sensors are usually cross-sensitive to CO2. Sometimes it's the other way around as well. But here's where the job was. So these are the nighttime peaks, like I said, unventilated bedroom. The job is over here. And so this is the highest spike that we got, so 486. And you can see that's right in the same ballpark of what the rest of the house is seeing. So this was on the second floor of the house. I didn't move them when we were spraying in the third, it's a two and a half story house. The job is right here. And then you can kind of tell where we left the house unoccupied because there's no nighttime peaks. So they didn't sleep in the house these couple of days. And then we're back to nighttime peaks. So this is what we have found consistently in watching a number of these jobs. If you ventilate well, the VOC spikes never get above normal levels. Now let's look at another one. Here's another spray foam job that we did. We foamed the attic here. So again, where's the job? So this is zoomed out, this is looking at basically a month. So zooming in, this is a week. This was kind of fun. So here's the job. You can see we got a little bit of a spike. And this spike here was likely when I put the house into depressurization. So I turned the blower door around that I sucked out rather than blowing in, where I've been blowing in all day. And then a couple of days later, I came back to do quality control. And I ran negative pressure for a long time then. So I was pulling all that foam off-gassing downstairs where the foobot could catch it up. So I drove it up quite a bit. As I left, I suggested leaving the windows cracked for ventilation. It was still a fairly temperate time of the years. You can see here, it was right about the time of years I'm recording this video now, three years later. And the windows were cracked. I went to a conference and was watching what was going on, keeping an eye on the foobot here. And I saw the level spike. And I texted my client and said, did you close the windows? And he was kind of freaked out by it at first, like I'm just watching the foobot level. So all of a sudden, everything went up. So it takes time to ventilate. And you can see that the levels came back up. And then it took them a while to come back down. So that's once again, well, this is about six days. So it takes about two weeks to fully cure. So you need to be ventilating for two weeks. But at least during the job, you can blow an awful lot of the garbage out. And after that, you want to have windows open. So ballpark two weeks is what you want to look at. So what we learned from that is pressurize the blower door during install. That is standard practice for us now. And open the windows or do some kind of ventilation for two weeks or so post job. So those are the three examples of using indoor air quality monitors. And we found those, these were, this was really interesting and really useful. And this really helped us understand what we were doing, what was working and what wasn't. So I can't recommend playing with a few of these. And I really do recommend getting multiples. So if you're going to buy one, try not to get one, get two or three. And see what you can learn. Put them in different places of the house and see what you can learn. So just wanted to record that. Hope that was enjoyable and you learned something. I'll talk to you next time. I'm Nate Adams. Bye-bye.